<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div></div>
<script>let nub1=+prompt("唱跳rap");
let nub2=+prompt("篮球");
alert(nub1+nub2);
</script>
</body>
</html>